Secretary of State John Kerry says the U.S. is considering sanctions on people encouraging unrest in South Sudan, where political and sectarian violence has displaced more than 1 million people.

In an interview with VOA at the State Department Monday, Kerry said the Obama administration is "very, very closely" looking at possible sanctions, although he declined to specify whom the U.S. might target.

He said he believes the fighting in South Sudan, which began as a dispute over oil, power and ethnic rivalries, has now become personal. Fighting broke out in mid-December when President Salva Kiir accused his former deputy Riek Machar of attempting a coup.

Kerry told VOA the crisis in South Sudan is a tragedy, especially given how long South Sudan struggled to become an independent nation.

"This was a moment of great hope, and to see it tugged downwards by personal ambitions and personal animosities is really in many ways a betrayal of the trust of the people in their leaders," said Kerry.

The secretary said the U.S. is still hoping to end the ongoing clash between government and rebel forces through diplomacy.

On Wednesday, Kerry begins a trip to East Africa that will take him to Ethiopia's capital, Addis Ababa, where peace talks between South Sudan's government and rebel representatives have failed to make progress.

He also is scheduled to visit the Democratic Republic of Congo and Angola during the seven-day trip.

Kerry said the challenges of governance throughout the region are probably as significant today as they have been in a long time.

He said the Untied States is providing direct support to Nigeria's government, which is battling an Islamic insurgency in the country's north.

"It's very, very complicated, there's been violence and the government needs to be stronger and we're working to help strengthen it," said Kerry.

He said the fight against Islamic militants is an issue facing many countries in the region.

"It’s not just in Nigeria, it’s in Mali, it’s in Tunisia, it’s in Libya still. You’re seeing these tensions spread throughout the Magreb and the Sahel. And we are doing everything possible. We’ve augmented our presence, we’ve increased our assistance and we will continue to do so and to work with our friends, the French and others, in an effort to try to make a difference," he said.

On the topic of the Central Africa Republic, Kerry said it is regrettable that China and Russia did not support U.N. sanctions. He said Russia "has been objecting to almost every effort at the United Nations" and he said "without U.N. sanctions it is much more difficult to be able to take the steps we believe are necessary.”

The Central African Republic has been plagued by sectarian fighting that erupted in December, with mainly Christian militias clashing with Muslim rebels.

Kerry also spoke about the Democratic Republic of Congo, where he said the key to promoting stability is to ensure that rebels from the group M23 are disarmed. He said it is “very, very important that the people there have a sense that the international force is doing what it needs to do to disarm, to enforce the agreements.”